Using a tangentially viewing x-ray imaging crystal spectrometer, substantial co-current rotation driven by lower hybrid current drive（LHCD） at 4.6 GHz is observed on EAST tokamak. This study presents plasma rotation...Using a tangentially viewing x-ray imaging crystal spectrometer, substantial co-current rotation driven by lower hybrid current drive（LHCD） at 4.6 GHz is observed on EAST tokamak. This study presents plasma rotation behaviors with 4.6 GHz LHCD injection. Typically, the 10-20 km/s co-current rotation change and the transport of rotation velocity from edge to core are observed. The relationship between plasma parameters and rotation is also investigated, indicating that rotation decreases with increasing internal inductance（li） and increases with increasing safety factor（q0）. Hysteresis between rotation and Te plasma stored energy is observed, suggesting different response times between the electron heating and rotation acceleration by LHCD. A comparison between the rotations driven by 4.6 G LHCD and 2.45 G LHCD on EAST is also presented, in which higher frequency LHCD could induce more rotation changes.展开更多
Core plasma rotation of both L-mode and H-mode discharges with ion cyclotron range of frequency（ICRF） minority heating（MH） scheme was measured with a tangential X-ray imaging crystal spectrometer on EAST（Experime...Core plasma rotation of both L-mode and H-mode discharges with ion cyclotron range of frequency（ICRF） minority heating（MH） scheme was measured with a tangential X-ray imaging crystal spectrometer on EAST（Experimental Advanced Superconducting Tokamak）.Cocurrent central impurity toroidal rotation change was observed in ICRF-heated L-and H-mode plasmas.Rotation increment as high as 30 km/s was generated at ~1.7 MW ICRF power.Scaling results showed similar trend as the Rice scaling but with significant scattering,especially in L-mode plasmas.We varied the plasma current,toroidal field and magnetic configuration individually to study their effect on L-mode plasma rotation,while keeping the other major plasma parameters and heating unchanged during the scanning.It was found that larger plasma current could induce plasma rotation more efficiently.A scan of the toroidal magnetic field indicated that the largest rotation was obtained for on-axis ICRF heating.A comparison between lower-single-null（LSN）and double-null（DN） configurations showed that LSN discharges rendered a larger rotation change for the same power input and plasma parameters.展开更多
Q-switch for pulsing laser beam and Galvano scanner for rapid scanning laser beam were adapted to manipulate micro solid particles in a water droplet. The trapping of fine particles at micron-sized diameters by a YAG ...Q-switch for pulsing laser beam and Galvano scanner for rapid scanning laser beam were adapted to manipulate micro solid particles in a water droplet. The trapping of fine particles at micron-sized diameters by a YAG laser system, induced flows, and the induced motion of the particles by laser beam irradiations are discussed. Particle rotations are observed by using anisotropic micro objects, and moreover the rotational rate with clockwise direction is 22 r/min. The fragments of a cover glass were mixed in a water droplet, and their size and shape are uneven. The rotation of that non-spheres without scanning by the Galvano scanner is also observed in water.展开更多
基金Project supported by the National Magnetic Confinement Fusion Science Program of China(Grant Nos.2013GB112004 and 2015GB103002)the National Natural Science Foundation of China(Grant Nos.11405212 and 11261140328)the Major Program of Development Foundation of Hefei Center for Physical Science and Technology China(Grant No.2016FXZY008)
文摘Using a tangentially viewing x-ray imaging crystal spectrometer, substantial co-current rotation driven by lower hybrid current drive（LHCD） at 4.6 GHz is observed on EAST tokamak. This study presents plasma rotation behaviors with 4.6 GHz LHCD injection. Typically, the 10-20 km/s co-current rotation change and the transport of rotation velocity from edge to core are observed. The relationship between plasma parameters and rotation is also investigated, indicating that rotation decreases with increasing internal inductance（li） and increases with increasing safety factor（q0）. Hysteresis between rotation and Te plasma stored energy is observed, suggesting different response times between the electron heating and rotation acceleration by LHCD. A comparison between the rotations driven by 4.6 G LHCD and 2.45 G LHCD on EAST is also presented, in which higher frequency LHCD could induce more rotation changes.
基金supported by the National Magnetic Confinement Fusion Science Program of China(Nos.2013GB112004 and 2015GB103002)National Natural Science Foundation of China(Nos.11175208,11305212,11375235,11405212 and 11261140328)+1 种基金the Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology(2014FXCX003)Brain Korea 21 Program for Leading Universities&Students(BK21 PLUS)
文摘Core plasma rotation of both L-mode and H-mode discharges with ion cyclotron range of frequency（ICRF） minority heating（MH） scheme was measured with a tangential X-ray imaging crystal spectrometer on EAST（Experimental Advanced Superconducting Tokamak）.Cocurrent central impurity toroidal rotation change was observed in ICRF-heated L-and H-mode plasmas.Rotation increment as high as 30 km/s was generated at ~1.7 MW ICRF power.Scaling results showed similar trend as the Rice scaling but with significant scattering,especially in L-mode plasmas.We varied the plasma current,toroidal field and magnetic configuration individually to study their effect on L-mode plasma rotation,while keeping the other major plasma parameters and heating unchanged during the scanning.It was found that larger plasma current could induce plasma rotation more efficiently.A scan of the toroidal magnetic field indicated that the largest rotation was obtained for on-axis ICRF heating.A comparison between lower-single-null（LSN）and double-null（DN） configurations showed that LSN discharges rendered a larger rotation change for the same power input and plasma parameters.
文摘Q-switch for pulsing laser beam and Galvano scanner for rapid scanning laser beam were adapted to manipulate micro solid particles in a water droplet. The trapping of fine particles at micron-sized diameters by a YAG laser system, induced flows, and the induced motion of the particles by laser beam irradiations are discussed. Particle rotations are observed by using anisotropic micro objects, and moreover the rotational rate with clockwise direction is 22 r/min. The fragments of a cover glass were mixed in a water droplet, and their size and shape are uneven. The rotation of that non-spheres without scanning by the Galvano scanner is also observed in water.
